Lithium in the era of prolonged-release formulations: a position paper

In the treatment of bipolar disorder, lithium still represents the golden standard, as it is used as a first-line therapy in both the prophylaxis and treatment of acute mania, and as an augmentation treatment to increase the efficacy of antidepressants in unresponsive patients. It is also effective in reducing the risk of suicide in patients with and without bipolar disorder, and it exerts immunomodulatory and neuroprotective actions.
Despite these facts, lithium has been greatly underutilized in mood disorders for a number of reasons that include a narrow therapeutic window, the existence of various ranges within which it is necessary to keep its values, and a series of collateral effects that need to be cautiously handled.
According to scientific literature, we hypothesize that prolonged-release (PR) lithium formulations may provide a number of potential advantages over immediate-release (IR) formulations, including:
1. more stable lithium serum concentrations while reaching the effective interval and on the long term; 2. a reduced risk of some adverse events, specifically with regards to renal functions, determining an improving in adherence, and 3. a more convenient dosing regimen, that may also improve adherence to therapy. Future trials comparing compliance rates, efficacy and adverse events associated with the PR and IR lithium formulations are required to confirm potential advantages that could further widen the clinical use of lithium.